Chicken with Sour Cream

how to cook(prepare)Chicken with Sour Cream ?
Ingredients

Bone less Chicken : 1.25 lbs
Raja Tandoor Mashala : 3 and 1/2 table spoon
Salt
Onion : 3
Ginger : 1 and 1/2 inch piece
Garlic : 8-10 piece
Green Chilli : 6
Tomato : 1 small
Cooking oil : 4/5 spoon
Method
Cut chicken into small pieces ( 1 inch suggested ), wash and rap it with a piece of paper towel to remove the extra water from the chicken.
Cut it into small piece of onion, garlic and green chilli.
Grate the ginger.
Cut the tomato into 4 pieces
Place the pan on the gas burner, let it be there for few minutes then pour oil and let the oil be warm.
Pour garlic into the oil and stir until golden brown, then mix onion and green chilli and stir carefully until it becomes golden brown, and then mix ginger and tomato and stir for few seconds.
Add chicken into that and stir for few minutes, then add raja tandoor masala and salt and stir until chicken started releasing little water. Then cover it for few minutes and then you can add little water (50 ml) if you want to have gravy. But don't mix more water. When the chicken will be fully cooked then take 4/5 spoon of sour creak into a bowl ( you can take more if you want to make it more sour ) then mix 2 spoon of water and stir until whole sour cream in the bowl becomes a thick gravy. Switch off the gas burner and pour the sour cream gravy in to the cooked chicken and stir it well so that it will mix with the whole chicken.
Serve with the Roti or Nan.